Aspirating nozzle assembly



June 20, 1967 Q BRIGGS 3,326,471

ASPIRATING NOZZLE ASSEMBLY Filed Feb. 11, 1965 INVENTOR (FY/667V! C.32/665 ATTORNEYJ United States Patent 3,326,471 ASPIRATING NOZZLEASSEMBLY Eugene C. Briggs, Dayton, Ohio, assignor to MasterConsolidated, Ind, Dayton, Ohio, a corporation of Ohio Filed Feb. 11,1965, Ser. No. 431,862 6 Claims. (Cl. 239406) This invention relates toimprovements in siphon type nozzles and more particularly to simplifyingsuch nozzle structures and rendering them adaptable to a wider varietyof applications. Embodiments feature low cost assembly. They areuniquely designed to facilitate an interchange of orifice tubes offeringdifierent flow rates, the advantages of which are believed obvious.

A primary object of the invention is to provide a siphon type nozzleunit which is more economical to fabricate, more efiicient andsatisfactory in use, adaptable to a wider variety of applications andunlikely to malfunction.

Another object of the invention is to simplify the assem bly anddisassembly of aspirating type nozzle units so as to render them moreversatile in application.

A further object of the invention is to provide a siphon type nozzleunit with a more readily replaceable orifice tube.

An additional object of the invention is to provide a novel siphon typenozzle unit wherein a change in flow rate may be simply and quicklyachieved.

Another object of the invention is to provide a siphon type nozzle unitpossessing the advantageous structural features, the inherentmeritorious characteristics and the means and mode of use hereindescribed.

With the above and other incidental objects in View as will more fullyappear in the specification, the invention intended to be protected byLetters Patent consists of the features of construction, the parts andcombinations thereof, and the mode of operation as hereinafter describedor illustrated in the accompanying drawings, or their equivalents.

Referring to the accompanying drawing wherein is shown one but obviouslynot necessarily the only form of embodiment of the invention,

FIG. 1 is a longitudinal section of a nozzle unit in accordance with theinvention;

FIG. 2 is a detail of the nozzle stem, shown partly in section;

FIG. 3 is an end view of the stem; and

FIG. 4 is a view of the complete nozzle unit.

Like parts are indicated by similar characters of reference throughoutthe several views.

The nozzle unit illustrated features extreme simplicity of construction.It consists of a stem 10, cap 11 and an orifice tube 12.

The stem is a tubular body featuring a central bore 13 of uniformdiameter from its entrance end 14 to a plane adjacent and spaced fromits discharge end 15. From this plane the bore 13 is conically reducedfor a short section 16 which is followed by a short uniformlycylindrical orifice section 17 terminating in a conically expanded lip18.

The exterior of the body providing the stem 10 features a uniformdiameter from its entrance end to a shoulder 19 defined by acylindrically expanded section 20 at its approximate center. The section20 is followed by a conically tapered section 2-1 convergent to a shortcylindrical section 22. The section 22 terminates in a shoulder 23defined by a flange portion 24. The flange portion 24 is followed by acylindrically expanded stem portion 25 featuring an undercut 26 at itsjuncture with the flange and terminating at its end remote from theflange in a shoulder 25'. The relative diameters of the stem portion 25and flange 24 are such to define a narrow annular abutment 3,326,471Patented June 20, 1967 surface 27 on the face of the flange mostadjacent and peripheral to the stem portion 25. The end of portion 25terminates in a chamfer in spaced relation to the discharge end of thestem. The outer diameter of the stem beyond the portion 25 is generallyequal to that of the stem at its entrance end except at its dischargeextremity which features a conically convergent taper 28.

As will be readily apparent from the drawings the flange 24 defines thelargest radial projection on the stem 10.

The cap 11 has a cup shape, its inner surface forming a cylindrical wallsection 29 having one diameter adjacent its head 30 and a relativelylarger diameter adjacent its open end. Its head 30 is dished to acentral aperture 31 arranged coaxial with the open end of the cap.

The outer surface of the cap wall is threaded from its open end,coextensively with the diametrically enlarged portion of its innersurface. This threaded port-ion is followed by a projected flange 32beyond which the head of the cap has a conically convergent form.

In assembling the cap 11 to the stem 10, the stem portion 25 is pressfit to nest within the diametrically enlarged open end of the cap, inthe process of which the open end of the cap wall achieves a sealingabutment with the annular surface 27 on the stem flange 24. Thispositions the discharge portion of the stem 10 interiorly of and inconcentric spaced relation to the cap wall 29. The discharge extremityof the stem positions in axially spaced relation to the cap aperture 31and the orifice 17 aligns coaxial therewith. The limitation of the capby abutment of the peripheral wall thereof with the stem surface 27insures the formation of a chamber 35 about the nested discharge end ofthe stem.

As seen in FIG. 1 of the drawings, the orifice tube 12 is press fit atone end in the orifice 17 of the stem '10 while its other end positionswithin the aperture 31 of the cap 11 as the cap is applied to the stem.In the example illustrated the discharge end of the tube 12 falls justshort of the outermost surface 33 of the head end of the cap.

The stem 10 has four equidistantly spaced skewed passages 34 angled at30 to the stem exis, opening at one end from the shoulder 23 of flange24 and at their opposite ends from the shoulder 25' to the interior ofthe chamber 35.

It is a unique feature of the nozzle unit above described that one mayhave a number of orifice tubes 12 having difi'erent size bores, each ofwhich may be similarly press fit in the orifice 17 of the stem 10. Thetubes may be easily interchanged to achieve a desired flow rate with thesame basic cap and stem.

The described nozzle unit may be readily applied in a conventionalburner unit, the entrance end of the stem 10 being coupled to a fuelline and the entrance ends of the passages 34 exposed to a pressuredflow of air.

The passages 34 are operable to produce an optimum channelling of air toswirl into the chamber 35 and about the discharge end of the stem. Thisswirling flow of air exits at a high velocity through the limitedpassage between the discharge end of the orifice tube 12 and the wall ofthe aperture 31 in the cap 11. The tube is thereby exposed to a highlydeveloped suction which draws fuel therethrough from the fuel source.The swirl characteristics are such to thoroughly atomize the fuel as itexits from the tube.

Thus, the invention structure is not only simple but highly effective inuse. It features a ready interchangeability of its orifice tube which bya proper selection of its flow passage may obviously achieve any desiredresult.

From the above description it will be apparent that there is thusprovided a device of the character described possessing the particularfeatures of advantage before enumerated as desirable, but whichobviously is susceptible of modification in its form, proportions,detail construction and arrangement of parts without departing from theprinciple involved or sacrificing any of its advantages.

While in order to comply with the statute the invention has beendescribed in language more or less specific as to structural features,it is to be understood that the invention is not limited to the specificfeatures shown, but that the means and construction herein disclosedcomprise but one of several modes of putting the invention into effect,and the invention is therefore claimed in any of its forms ormodifications within the legitimate and valid scope of the appendedclaims.

Having thus described my invention, I claim:

1. An aspirating nozzle for a fuel burning space heater or the likeconsisting per se of a tubular stem, a selective control tube and a cap,said stem having its one end adapted for coupling to a fuel flow line,said selective control tube having a releasable slip fit to and formingan extension of the other end of said tubular stem, said stem having anintegrally formed radially projected flange means on a section of itsexterior wall, said cap rnounting in an enclosing spaced relation tosaid other end of said stem and the slip fit control tube to have itsopen end seat in a sealed abutting relation to said flange means, saidcap forming a flow chamber thereby, passages in said flange means fordelivering a pressured flowof air to and through said chamber, said caphaving an aperture coaxial with the discharge end of said control tubeand the control-tube defining with the portion of said cap forming saidaperture a restricted flow path for high velocity movement of air fromsaid chamber to aspirate fuel through said stem and said control tube,the slip fit of said control tube facilitating a quick interchangethereof to suit the application of said nozzle.

2. A nozzle as in claim 1 characterized by said control tube being aflow restricting device the projected extremity of which terminateswithin the aperture in said cap.

3. A nozzle as set forth in claim 1 characterized by said flange meansbeing stepped to have a relatively reduced portion fit to plug the openend of said cap while the remainder serves as a limiting abutment forsaid cap.

4. An aspirating nozzle for a fuel burning space heater or the like,including a tubular stem having a through longitudinal bore therein forflow of a fluid fuel through saidstem, said stem having inlet anddischarge ends with respect to the direction of fluid flow, a cup shapedcap receiving the discharge end of said stem through its open end, theclosed end of said cap providing an aperture aligned with the bore insaid stem, flange means occupying an intermediate position on theexterior of said stem and including a portion to Which the open end ofsaid cap seats to limit relative approaching motion of said stem and capand further including another portion received in said cap to space thedischarge end of said stern radially from said cap, the first saidportion being positioned to space the inner extremity of said dischargeend of said stem longitudinally from the closed end of said cap, saidflange means defining in said cap a chamber enclosing the discharge endof saidstem, flow passage means for introducing air under pressure intosaid charmher to escape through the aperture in the closed end of saidcap, and an orifice tube interchangeably installed in the discharge endof said stem as an extension of the bore therein and bridging saidchamber to extend at least into said aperture in the closed end of saidcap, said aperture exceeding in diameter the outside diameter of saidtube.

5. An aspirating nozzle according to claim 4, characterized in that saidflow passage means comprises openings formed angularly in said flangemeans to produce a swirling flow of air in said chamber.

6. An aspirating nozzle according to claim 4, characterized in that saidtube projects axially a substantial distance from said stem facilitatingits manipulation for Withdrawal from and replacement in said stem.

References Cited UNITED STATES PATENTS 1,401,880 12/1921 Connelly 2394053,215,351 11/1965 Briggs 239-406 3,226,037 12/1965 Biber et al. 239405EVERETT W. KIRBY, Primary Examiner.

1. AN ASPIRATING NOZZLE FOR A FUEL BURNING SPACE HEATER OR THE LIKECONSISTING PER SE OF A TUBULAR STEM, A SELECTIVE CONTROL TUBE AND A CAP,SAID STEM HAVING ITS ONE END ADAPTED FOR COUPLING TO A FUEL FLOW LINE,SAID SELECTIVE CONTROL TUBE HAVING A RELEASABLE SLIP FIT TO AND FORMINGAN EXTENSION OF THE OTHER END OF SAID TUBULAR STEM, SAID STEM HAVING ANINTEGRALLY FORMED RADIALLY PROJECTED FLANGE MEANS ON A SECTION OF ITSEXTERIOR WALL, SAID CAP MOUNTING IN AN ENCLOSING SPACED RELATION TO SAIDOTHER END OF SAID STEM AND THE SLIP FIT CONTROL TUBE TO HAVE ITS OPENEND SEAT IN A SEALED ABUTTING RELATION TO SAID FLANGE MEANS, SAID CAPFORMING A FLOW CHAMBER THEREBY, PASSAGES IN SAID FLANGE MEANS FORDELIVERING A PRESSURED FLOW OF AIR TO AND THROUGH SAID CHAMBER, SAID CAPHAVING AN APERTURE COAXIAL WITH THE DISCHARGE END OF SAID CONTROL TUBEAND THE CONTROL TUBE DEFINING WITH THE PORTION OF SAID CAP FORMING SAIDAPERTURE A RESTRICTED FLOW PATH FOR HIGH VELOCITY MOVEMENT OF AIR FROMSAID CHAMBER TO ASPIRATE FUEL THROUGH SAID STEM AND SAID CONTROL TUBE,THE SLIP FIT OF SAID CONTROL TUBE FACILITATING A QUICK INTERCHANGETHEREOF TO SUIT THE APPLICATION OF SAID NOZZLE.